There are many anatomic biomechanical deficiencies of a foot that can be identified by a foot specialist: flat feet, raised arch, Morton's neuroma, foot inversion, foot eversion, hammer toes, corns, calluses, heel pain, plantar fasciitis, heel spur syndrome, etc. Some of these deficiencies may be interrelated. For example, a raised arch may cause other problems such as corns, calluses or heel pains as walking pressure is not properly distributed as compared to a normal foot. Other problems such as hammer toes may be caused by the type of footwear that is used, such as high heels or very tight shoes. Furthermore, foot deficiencies may also cause problems or deficiencies in other parts of the body, particularly in the legs and the back of a person.
Foot orthosis or insoles are used to support a human foot in footwear, and have been known for quite some time in the field. However, none has proven satisfactory for adequately correcting the most common anatomic biomechanical deficiencies of the foot and ensuing body deficiencies.
Foot orthosis can generally be classified in two kinds. The first kind of foot orthosis is manufactured on a mass production scale. This kind of foot orthosis is not adapted to properly correct a person's biomechanical foot deficiencies because each person has different kinds of foot deficiencies. For example, U.S. Pat. No. 4,338,734 (SCHWARTZ) and U.S. Pat. No. 6,282,816 (ROSENDAHL) disclose different kinds of foot orthosis or insoles that are made on a mass production basis.
Also known in the art, there is U.S. Pat. No. 6,173,511 and international patent publication No. WO 97/24041 (PERRAULT) both of which disclose a foot orthosis formed of a monolithic shell made of a semi-rigid, resilient plastic substance characterized in that it has a rear part provided with a pair of horns that curve around a large ovoid notch. Although the US patent claims that the foot orthosis can compensate for podiatric deficiencies, it has not proven satisfactory in terms of patient comfort and actual compensation for the deficiencies due to its general design and choice of manufacturing materials. Indeed, because such orthosis is made of a hard plastic extending from the back of the heel up to the toes, it does not allow making compensations or corrections such as, for example, heel corrections, metatarsal corrections, inversion and eversion corrections, etc.
U.S. Pat. No. 3,995,002 (BROWN); U.S. Pat. No. 4,513,518 (JALBERT); U.S. Pat. No. 4,688,338 (BROWN); U.S. Pat. No. 4,756,096 (MEYER); U.S. Pat. No. 4,868,945 (DEBETTIGNIES); U.S. Pat. No. 5,003,708 (DALEY); U.S. Pat. No. 5,282,326 (SCHROER); U.S. Pat. No. 5,958,546 (MARDIX) and U.S. Pat. No. 6,195,917 (DIECKHAUS) disclose different kinds of foot orthosis or insoles, some of which are actually custom made. However, none of the foot orthosis or insoles disclosed can be used with satisfactory results to correct for anatomic biomechanical deficiencies of a person's foot.